Can children and adolescents be asked for their weight and height?

BERRA S; TEBÉ C; BRUIL J; ERHART M; RAVENS-SIEBERER U; RAJMIL L

Barcelona (España)

Congreso; I World Congress of Public Health Nutrition.; 2006

International Union of Nutritional Sciences.

Objective: To analyze missing values and outliers in youth- and parent-reported weight (W) and height (H), as well as correlations and differences between them. Methods: Data come from representative samples of 8-18 years old population of 9 countries participating in the European KIDSCREEN project. Youths and parents filled in questionnaires at home (n=10,301) or at school (n=2,889). Percentage of missing values and outliers were obtained for youth- and parent-reported W and H, as well as correlations and differences between them by age, sex, BMI category (from youth-reported W&H, and according to IOTF recommended cut-off-points for international comparisons), and method of questionnaire administration. Results: Missing values were more frequent in parents (W=7.4%; H=6.5%) than in youths (W=3.7%; H=4.0%), without differences between children and adolescents. Percentages of outliers were higher in adolescent girls (W=3.9%; H=1.4%). Missing values figures were lower when youth questionnaires were filled-in at home (W=3.5%; H=2.9%) than in schools (W=4.1%; H=3.9%). Correlations between youth- and parent-reported W and H ranged between 0.97 and 0.99, depending on sex or age, and diminished to 0.77 (W in adolescents) and 0.87 (H in children) in obese youths. Youth-parent mean differences were higher in obese adolescents (W=2.9 kg in boys; 5.6 kg in girls), boys (H=-2.95 in children; -1.7 cm in adolescents), but they were related to report error in 9 cases (<0.001% of the sample). Conclusions: Lower percentages of missing values, very high correlations and few differences in the reported measures indicate that youths can be asked for their weight and height instead of their parents. Administration in households prevents missing values.